In Australia the movie is M15+ rated. Where did you get the idea that Harry Potter was only for little children?

Because he and people like him are ignorant. They are well written stories and aren't really "kiddish" at all (well, maybe the 1st one, but I only saw that one because of my nieces and nephews), but it was still good enough for me to want to see the rest.

watched it yesterday and it was a let-down IMO. What I always hated about the movies was that they missed all those great sub-plots/stories from the book. Mrs Weasly's visions of her family dying should have been in there for better understanding. Harry and the rest visiting St. Mungo's and their encounter with Neville, his parents and grandma, instead of Neville just telling him after DA.
Also, they changed A LOT about Umbridge and how she ran school.

Aside from all that, the movie didn't have a good feel to it. First half was more like different episodes put together, wasn't cohesive at all. The 3rd movie was way better in that regard, not to mention the Lord of the Rings trilogy, which did a far better job, though I realizy it was 10 hours long

I liked it quite a bit. Not the best one of them but not the worst either. I'd say its maybe the 3rd best one for me. PoA, GoF, OotP, P/SS, CoS, P/SS. I absolutely do NOT miss Chris Columbus one bit.

They leave a bunch out but Potter fans need not complain compared to what happens to other books to film.

Michael Crichton books get cut to pieces so bad it hurts. Even Jurassic Park was overhauled quite a bit. Hell, in the book, the islands owner and Jeff Goldblum's character die while the lawyer that gets eaten off the toilet (in the movie) turns into a hardcore action hero. Even the book Lost World that MC wrote to explain how Goldblum didn't die had massive changes. Hint, there was no TRex eating people in front of video stores. Don't even get me started on what they did to Sphere (wasting a great cast in the process).

Plus if you still feel like complaining, look what happened to the poor Lemony Snicket readers. They crammed 3 books into one movie and hired an actor (Jim Carrey) as the main villain who openly says he doesn't do sequels to his flicks b/c he hated Ace 2 (which was the only movie I have ever fallen asleep in).